Of course, an attractive garden does not need glass. You can grow suitable vegetables at the right time, plant subjects which are hardy in our climate, and buy in plants which need a warm start, all without providing protection of any kind. All glass is expensive, both in its initial provision and in upkeep, and especially to heat, so if your only intention is to raise a few bedding plants or grow your own tomatoes, do not bother with it. If you long to grow exotic vegetables, choose varieties that will grow outdoors. It is often argued that you can save a lot of money for the outlay of a greenhouse but this is true only if you are prepared to go into the matter scientifically, and produce enough plants or crops to be able to sell your surplus economically. Otherwise greenhouse gardening is an interesting but expensive hobby.
The same applies to cloches and cold frames. If you can knock something up out of a roll of polythene and some wire, or some old glazed windows and second-hand timber, then you are on to a winner, but if you intend to equip yourself with one or more of the very good but comparatively pricey items now available, you must want early or late vegetables very badly or have a strong urge to propagate masses of plants, to justify the cost.
Conservatories are a rather different matter, however. Their popularity has rocketed in recent years and they are no longer glorified lean-to greenhouses but aesthetic and functional additional rooms. While these are in an even higher price bracket than the ordinary free-standing greenhouse, not only do they enable you to indulge whichever aspects of indoor gardening take your fancy, they bring the outdoors inside the home.
Gardening under glass is a whole science in itself, and it is beyond the scope of this blog to do more than scrape the surface of the subject, but included will be a list of what you could consider if you feel the urge to experiment, and suggestions for how they can be used, over the coming week.